It is known from the prior art to convert the light e.g. of blue LEDs into white mixed light by means of color conversion, wherein a phosphor absorbs the light emitted by the light-emitting diode chip and converts it into light having a longer wavelength. From a blue light generated by an LED chip, if appropriate in combination with a further (for example red) LED chip, white light can thus be generated.
A light-emitting diode arrangement 60 shown in FIG. 6 is already known from the prior art, in which light-emitting diode arrangement a light-emitting diode chip 61 is arranged on a base 62 comprising an insulation layer 63 and an electrically conductive layer having conductor tracks 64. The chip 61 is situated on one conductor track and is additionally connected to a further conductor track by means of a bonding wire 65. A wall 66 is provided around the chip 61. In accordance with the so-called “dam and fill” technique, the inner region defined by said wall is filled with a color conversion material 67, wherein the light-emitting diode chip 61 is surrounded by said material.
What is disadvantageous about this configuration, however, is the heat dissipation proceeding from the light-emitting diode chip 61. Air or gas is actually situated in the light emission direction and around the walls. Although the chip on its underside is in direct contact with a thermally conductive conductor track, the latter is hardly suitable for transferring heat on account of its size. An insulation layer 63 is provided in the lower region of the light-emitting diode arrangement 60, said insulation layer impairing a possible dissipation of heat.
For better regulation of the temperature within the light-emitting diode arrangement 60, a further arrangement 70 shown in FIG. 7 is known from the prior art, in which arrangement a coupler plate 71 several millimeters thick is used as a heat sink, said coupler plate being coated highly reflectively in the light emission direction at least on the top side. A circular depression is deep-drawn in the center of this heat sink plate, in which depression a plurality of series-connected light-emitting diode chips 72 are adhesively bonded. Afterward, the depression was potted virtually flush with the color conversion medium 73, e.g. phosphor.
This configuration has the advantage that the heat transfer from the light-emitting diode chips 72 to the heat sink is virtually optimal. However, there is the problem that this configuration does not satisfy requirements in respect of the dielectric strength. In the case of the known design, therefore, an undesired voltage breakdown can disadvantageously occur.
Accordingly, the present invention is based on the object of specifying a possibility for realizing a light-emitting diode arrangement in which a good compromise between heat dissipation and voltage endurance is ensured. In particular, a good temperature regulation or heat dissipation and a high dielectric strength are intended to be achievable.